The 30-year-old victim, who is Asian, was in Glasgow's Gordon Street when the incident happened shortly before midnight on Saturday.
He was outside the Co-op shop when he was approached by the suspect, who started shouting racist comments and then seriously assaulted him.
The victim received treatment at hospital for face and shoulder injuries.
Police Scotland officers are appealing for information and have issued a description of the suspect.
He is said to be white, 6ft and of stocky build. He was wearing a light-coloured top.
Detective Constable Tony Brady, of city centre police office, said: "Since this incident was reported to police, officers have been carrying out enquiries in the local area and studying CCTV footage in an effort to gather more information on this crime and the man responsible.
"Gordon Street would have been busy with people on a night-out and I would urge anyone who witnessed this crime, or has any information that may assist police enquiries, to contact Police Scotland on 101."
Crimestoppers can also be contacted anonymously on 0800 555 111.